Development and Characterisation of Gastroretentive Solid Dosage Form Based on Melt Foaming.

Area of Science:

• Pharmaceutical Technology
• Drug Delivery Systems
• Materials Science

Background:

• Increased gastric residence time enhances bioavailability for drugs with narrow absorption windows.
• Low-density floating formulations offer a strategy to prolong drug release by resisting gastric emptying.

Purpose of the Study:

• To develop a novel melt foaming technology for producing low-density floating drug formulations.
• To create sustained-release metronidazole formulations using melt foaming.

Main Methods:

• Melt foaming of metronidazole dispersion using PEG 4000, Labrasol, and stearic acid at 53°C.
• Characterization of foam structure using Scanning Electron Microscopy (SEM) and MicroCT scans.
• Evaluation of drug release kinetics and matrix erosion using texture analysis.

Main Results:

• A closed-cell, low-density foam structure with micron-sized voids was successfully created.
• Stearic acid improved foamability and preserved matrix integrity, reducing erosion.
• Metronidazole release followed the Korsmeyer-Peppas model, with matrix erosion as the primary release mechanism.

Conclusions:

• The melt foaming technology effectively produces low-density floating formulations with sustained drug release.
• The developed formulations demonstrate potential for improving the bioavailability of drugs with narrow absorption windows.
• Stearic acid is crucial for maintaining the structural integrity and controlled erosion of the floating matrix.